Imaging radar echo adaptive gain control method and device, and storage medium

Abstract

The invention discloses an imaging radar echo adaptive gain control method and device, and a storage medium. An AD acquisition module acquires echo signals of each sampling point acquired by an echo receiving channel within a set time period length; the amplitude of echo data is calculated, and a histogram is constructed; the histogram is converted into a binary histogram; obtaining a binary histogram of the echo template; selecting the gain state corresponding to the echo template corresponding to the maximum correlation coefficient as the gain state of the collected echo data; and adjusting the gain of the echo receiving channel. According to the method, the echo data is calculated to obtain the histogram, the threshold value M is set through the number of sampling points to obtain the binary histogram of the echo data, other information of the data does not need to be considered, the size of the echo data is judged through the correlation coefficient of the binary histogram of the echo template, and when no AGC circuit exists, the detection accuracy is improved. The gain state of the echo receiving channel can be determined by the digital end according to the state of the echo.

Description

Technical Field

[0001] The present invention belongs to the technical field of radar signal processing, and in particular relates to an imaging radar echo adaptive gain control method, device and storage medium. Background Art

[0002] Radar imaging technology is increasingly developing in the direction of high resolution, high integration, and high reliability, which places higher requirements on radar sampling channels and data transmission speed. After the AD sampling device samples and quantifies the radar echo, it performs a series of digital signal processing such as digital demodulation, extraction filtering, beamforming, FFT, and pulse compression. At the same time, a SAR image has echo data of several hundred GB, or even TB in size. In order to avoid errors such as system failures and abnormal parameter configuration, which lead to abnormal echo status and waste of manpower and material resources, it is particularly important to detect the echo data status.

[0003] At present, the transmission link of radar echo data is based on high-speed interface transmission, and the echo data volume is large. The status monitoring of echo data in the early debugging process is based on the connection debugging simulator to capture the status. This monitoring method can quickly locate problems in the early debugging process, but it will waste human resources in the mid-term debugging, and this monitoring method is no longer applicable in the later product delivery.

[0004] Another common method is to count the size of the echo data. If it is below the lower threshold of valid data, it is noise. If it is above the upper threshold, it is overflow. If it is between the thresholds, it is valid data. For example, the invention patent application with application number 202010512096.5 discloses a radar echo data processing method, which replaces the corresponding initial judgment parameter according to at least one of the determined top height echo threshold, vertical gradient value, and echo change threshold, and screens the radar base data according to the replaced initial judgment parameter. Because the size of the echo data is counted, more resources are occupied and the echo processing delay is large.

[0005] In addition, the link gain plays a key role in echo monitoring. When the link gain is too small, the system sensitivity is reduced and the target monitoring threshold cannot be reached; when the link gain is too large, the target echo and other background targets will be saturated, making it difficult to distinguish the target echo. Therefore, by determining the state of the collected echo, the link gain can be determined, and the link gain can be adjusted to monitor the target echo without causing signal overload saturation. Summary of the invention

[0006] The purpose of the present invention is to provide an imaging radar echo adaptive gain control method, device and storage medium for the above-mentioned problems existing in the prior art. The signal amplitude of the echo data after AD acquisition is obtained, the binary histogram is calculated, and the autocorrelation calculation is performed with the echo templates representing different gain states. The echo templates are distributed from weak to strong according to the gain. The state of the echo data is determined by the autocorrelation calculation, indicating the gain of the echo receiving channel link, and the gain state is adjusted to obtain the echo data in the best state.

[0007] The present invention solves the above technical problems through the following technical means:

[0008] An imaging radar echo adaptive gain control method comprises the following steps:

[0009] Step 1: The AD acquisition module acquires the echo signals of each sampling point acquired by the echo receiving channel within the set time period;

[0010] Step 2: Calculate the real data and imaginary data of the echo data according to the echo data of each sampling point, further calculate the amplitude of the echo data, and construct a histogram. The abscissa of the histogram is the bit point, and the ordinate of the histogram is the number of echo data merged into the echo data amplitude corresponding to the bit point;

[0011] Step 3: Convert the histogram into a binary histogram;

[0012] Step 4: Obtain a plurality of binarized histograms of echo templates representing different gain states;

[0013] Step 5: Calculate the correlation coefficient between the binarized histogram obtained in step 3 and the binarized histograms of each echo template, and select the gain state corresponding to the echo template corresponding to the largest correlation coefficient as the gain state of the collected echo data corresponding to the binarized histogram obtained in step 3;

[0014] Step 6: According to the gain state of the collected echo data, adjust the gain of the echo receiving channel.

[0015] As described above, each bit in step 2 corresponds to an echo data amplitude. If the acquired echo data amplitude is between the echo data amplitudes represented by two bit points, the acquired echo data amplitude is merged to the nearest bit point.

[0016] The difference between the amplitudes of the echo data represented by the adjacent bit points on the horizontal axis of the histogram in step 2 is B / (2 N-1 ), N is the sampling bit number of the AD sampling module, and B is the input range amplitude of the AD acquisition module.

[0017] As described above, converting the histogram into a binary histogram includes: setting the threshold M to 10-20% of the number of sampling points within the set time period, setting the ordinate value of the echo data in the histogram that is greater than or equal to the set threshold M to 1, and setting the ordinate value of the echo data in the histogram that is less than the set threshold M to 0.

[0018] As mentioned above, the correlation coefficient is based on the following formula:

[0019]

[0020] R is the correlation coefficient, A is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram obtained in step 3 and the binary histogram of the echo template are equal to 0 after the modulo 2 operation, and D is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram obtained in step 3 and the binary histogram of the echo template are equal to 1 after the modulo 2 operation.

[0021] As mentioned above, the gain states include weak echo, best echo, and strong echo.

[0022] Adjusting the gain of the echo receiving channel in step 6 includes the following steps:

[0023] If the gain state of the collected echo data is a weak echo, the gain of the echo receiving channel is increased by the set gain step length, and the process returns to step 1;

[0024] If the gain state of the collected echo data is the best echo, the gain of the echo receiving channel does not need to be changed, and the process returns to step 1;

[0025] If the gain state of the collected echo data is a strong echo, the gain of the echo receiving channel is reduced by the set gain step size, and the process returns to step 1.

[0026] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned gain control method when executing the computer program.

[0027] A computer-readable storage medium stores a computer program, which implements the steps of the gain control method when executed by a processor.

[0028] A computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the gain control method are implemented.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The echo data is calculated to obtain a histogram, and then the threshold M is set by the number of sampling points to obtain a binary histogram of the echo data. There is no need to consider other information of the data. The size of the echo data is judged by the correlation coefficient with the binary histogram of the echo template. When there is no AGC circuit, the digital end can determine the gain state of the echo receiving channel according to the state of the echo.

[0031] The correlation coefficient is calculated between the binary histogram of the echo data transformation and the binary histogram of the echo template representing different gain states pre-written in the FPGA. Since the sampled echo data has been processed into a binary histogram, which is equivalent to a 0 / 1 sequence, the FPGA can obtain the relationship between the echo data and the pre-written echo template representing various gain states without too complicated processing, and adjust the gain state of the echo receiving channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0033] In order to facilitate those skilled in the art to understand and use the present invention, the present invention is further described in detail below in conjunction with embodiments. It should be understood that the implementation examples described herein are only used to illustrate and explain the present invention and are not used to limit the present invention.

[0034] Embodiment 1:

[0035] like Figure 1 The imaging radar echo adaptive gain control method comprises the following steps:

[0036] Step 1: Get echo data. The digital end collects the echo signal obtained by the echo receiving channel through the AD acquisition module, and obtains the echo data of each sampling point within the set time period by reading the data register of the AD acquisition module.

[0037] Step 2: Calculate the real data I and imaginary data Q of the echo data according to the echo data of each sampling point. Further calculate the echo data amplitude (I 2 +Q 2 ) 1 / 2 , construct a histogram, the horizontal axis of the histogram is the bit point, and the vertical axis of the histogram is the number of echo data merged into the echo data amplitude corresponding to the bit point.

[0038] The echo data amplitude within the set time period is converted into a histogram for statistics. In this embodiment, the AD acquisition module is a bipolar sampling module, which can collect input positive and negative analog signals. B is the input range amplitude of the AD acquisition module. The maximum amplitude absolute value of the positive and negative analog signals that the AD acquisition module can collect is the same, both of which are B. The highest bit in the data register of the bipolar AD acquisition module represents the sign bit. Each horizontal axis of the histogram is a bit point (bit), and each bit point (bit) corresponds to an echo data amplitude. The acquired echo data amplitude is merged into the echo data amplitude corresponding to each bit point. If the acquired echo data amplitude is between the echo data amplitudes represented by two bit points, the acquired echo data amplitude is merged to the nearest bit point (that is, the bit point with the smallest difference in echo data amplitude). The difference in echo data amplitudes represented by adjacent bit points on the horizontal axis is B / (2 N-1 ), N is the sampling bit number of the AD sampling module. For the bipolar AD sampling module, the highest bit is the sign bit, so the resolution is B / (2 N-1 ), the vertical axis of the histogram is the number of echo data corresponding to the bit point.

[0039] Step 3: Convert the histogram obtained in step 2 into a binary histogram whose ordinate contains only 0 and 1. First, set a threshold M according to the sampling points. The threshold M is set to 10-20% of the number of sampling points X within the set time period. Set the ordinate value of the echo data in the histogram that is greater than or equal to the set threshold M to 1, and set the ordinate value of the echo data in the histogram that is less than the set threshold M to 0, thereby generating a binary histogram. Convert the histogram into a binary histogram to facilitate the subsequent calculation of the correlation coefficient, so that the amount of calculation of the subsequent correlation coefficient is reduced. The above threshold M can also be adjusted according to actual conditions.

[0040] Step 4: Obtain multiple binarized histograms of echo templates representing different gain states. As a preferred solution, multiple binarized histograms of echo templates representing different gain states are pre-written into the FPGA. The difference in echo data amplitude represented by adjacent bit points on the horizontal axis of the binarized histogram of the echo template is the same as that of the binarized histogram in step 3. In this embodiment, the gain state includes weak echo, optimal echo, and strong echo.

[0041] Step 5: Calculate the correlation coefficient between the binarized histogram obtained in step 3 and the binarized histogram of each echo template, and obtain the correlation coefficient between the binarized histogram obtained in step 3 and the binarized histogram of each echo template. Select the gain state corresponding to the echo template corresponding to the largest correlation coefficient as the gain state of the collected echo data corresponding to the binarized histogram obtained in step 3.

[0042] The correlation coefficient R is based on the following formula:

[0043]

[0044] A is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram of the binary histogram and the echo template obtained in step 3 are equal to 0 after the modulo 2 operation, and D is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram of the binary histogram and the echo template obtained in step 3 are equal to 1 after the modulo 2 operation. It represents modulo 2 operation. The modulo 2 operation rule is

[0045] Step 6: According to the gain state of the collected echo data, adjust the gain of the echo receiving channel.

[0046] If the gain state of the collected echo data is a weak echo, the gain of the echo receiving channel is increased by the set gain step length, and the process returns to step 1;

[0047] If the gain state of the collected echo data is the best echo, the gain of the echo receiving channel does not need to be changed, and the process returns to step 1;

[0048] If the gain state of the collected echo data is a strong echo, the gain of the echo receiving channel is reduced by the set gain step size, and the process returns to step 1.

[0049] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0050] Embodiment 2:

[0051] This embodiment provides a computer device, including a memory and a processor. The memory stores a computer program. When the processor executes the computer program, each step in the above-mentioned embodiment 1 is implemented.

[0052] Embodiment 3:

[0053] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, each step in the above-mentioned embodiment 1 is implemented.

[0054] Embodiment 4:

[0055] A computer program product includes a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned embodiment 1 are implemented.

[0056] It should be noted that the embodiments described in the present invention are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the described embodiments or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the attached claims.

Claims

1. An imaging radar echo adaptive gain control method, characterized in that: The following steps are involved: Step 1: The AD acquisition module acquires the echo signals of each sampling point acquired by the echo receiving channel within the set time period; Step 2: Calculate the real data and imaginary data of the echo data according to the echo data of each sampling point, further calculate the amplitude of the echo data, and construct a histogram. The abscissa of the histogram is the bit point, and the ordinate of the histogram is the number of echo data merged into the echo data amplitude corresponding to the bit point; Step 3: Convert the histogram into a binary histogram; Step 4: Obtain a plurality of binarized histograms of echo templates representing different gain states; Step 5: Calculate the correlation coefficient between the binarized histogram obtained in step 3 and the binarized histograms of each echo template, and select the gain state corresponding to the echo template corresponding to the largest correlation coefficient as the gain state of the collected echo data corresponding to the binarized histogram obtained in step 3; Step 6: According to the gain state of the collected echo data, adjust the gain of the echo receiving channel.

2. The imaging radar echo adaptive gain control method according to claim 1, characterized in that: In step 2, each bit corresponds to an echo data amplitude. If the acquired echo data amplitude is between the echo data amplitudes represented by two bit points, the acquired echo data amplitude is merged to the nearest bit point.

3. The imaging radar echo adaptive gain control method according to claim 1, characterized in that: The difference between the amplitudes of the echo data represented by the adjacent bit points on the horizontal axis of the histogram in step 2 is B / (2 N-1 ), N is the sampling bit number of the AD sampling module, and B is the input range amplitude of the AD acquisition module.

4. The imaging radar echo adaptive gain control method according to claim 1, characterized in that: The step of converting the histogram into a binary histogram includes: setting the threshold M to 10-20% of the number of sampling points within the set time period, setting the ordinate value of the echo data in the histogram that is greater than or equal to the set threshold M to 1, and setting the ordinate value of the echo data in the histogram that is less than the set threshold M to 0.

5. The imaging radar echo adaptive gain control method according to claim 1, characterized in that: The correlation coefficient is based on the following formula: R is the correlation coefficient, A is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram obtained in step 3 and the binary histogram of the echo template are equal to 0 after the modulo 2 operation, and D is the number of bit points whose ordinate values ​​of the corresponding bit points of the binary histogram obtained in step 3 and the binary histogram of the echo template are equal to 1 after the modulo 2 operation.

6. The imaging radar echo adaptive gain control method according to claim 1, characterized in that: The gain states include weak echo, best echo, and strong echo, Adjusting the gain of the echo receiving channel in step 6 includes the following steps: If the gain state of the collected echo data is a weak echo, the gain of the echo receiving channel is increased by the set gain step length, and the process returns to step 1; If the gain state of the collected echo data is the best echo, the gain of the echo receiving channel does not need to be changed, and the process returns to step 1; If the gain state of the collected echo data is a strong echo, the gain of the echo receiving channel is reduced by the set gain step size, and the process returns to step 1.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the gain control method according to any one of claims 1 to 6 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the gain control method according to any one of claims 1 to 6 are implemented.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the gain control method according to any one of claims 1 to 6 are implemented.

Images